Pressure sensors, or sensors of other physical quantities such as temperature, density and so on, employing a vibrating member are already known. These sensors exploit the influence of the pressure, temperature and/or density conditions of the surrounding environment on the oscillation frequency and amplitude of the vibrating member, and obtain the variations of the physical quantity of interest from the measurement of the oscillation frequency and amplitude deviations from the expected values.
Sensors of the above kind are disclosed for instance in U.S. Pat. No. 5,152,173 “Optical Sensing System”, U.S. Pat. No. 5,426,981 “Vibrating Sensor” and U.S. Pat. No. 4,841,775 “Vibratory Transducer”.
Yet the known sensors are not suitable for applications in which miniaturising the sensor is necessary in order to measure the pressure in small-sized chambers or in situations where a non-miniaturised sensor could cause non-negligible perturbations on the surrounding environment.
Therefore, it is an object of the present invention to overcome the above drawbacks, by providing a pressure sensor having a very limited overall size, of the order of 102 μm. The pressure sensor as claimed in the appended claims achieves the above and other objects.